tire pressure on tow vehicle

[Bobbyg2013]

should I increase the rear tire pressure by 10 psi, on my truck's tires or leave at the suggested 35 psi that is shown on the sticker on the door jam?

[Briand]

Lots of misinformation and confusing information here. If you want to get the most miles out of your tires, most even wear and carry the heaviest load, then inflate tires to the MAXIMUM that they specify on the side wall. I have never had a tire that did not state 2 pressures. Min and max.

[Atlee]

That spare is probably the "donut" type. Temporary for use to get to a place to fix the real tire.

coolbreeze01 wrote:

APT wrote:
This sticker lists what the vehicle manufacturer recommends for tire pressures as a compromise of ride/handling and comfort. It also must be capable of handling the vehicle's load at GVWR.



Many people have experienced that a little higher pressure when the vehicle is closer to GVWR than unloaded provides a better ride and handling.

Worth noting that the spare is filled to 80psi. Curious what the OP's spare tire is aired too?

[BossCamper]

Pressure questions have been answered well here.
Just another story.
I traded for a new F150 and specified LT tires. Had been towing with P tires and was tired of getting sway just from the squishy tires!
Got the new truck home, and looked .... They had tires on it with a model name LT something or other. The tires were P rated.
Called them back and had to actually educate the salesman about the difference!
Got the correct tires (actually LT rated)on it a couple of days later.
I still can't believe they didn't know the difference, but were maybe hoping I didn't!

[BurbMan]

hawkeye-08 wrote:
To carry the load the tire is rated for, you need the max psi on the sidewall. If you are carrying less than that, adjust accordingly. P-metric tires are often filled to recommended pressure on door jamb sticker, but that is not for the max load, that is for comfort.

Partly true...The pressure listed on the door jamb sticker is not for "comfort", that is the pressure required to support the load of the vehicle and its contents loaded to the full GVWR.

If the tire says 44 psi max on the sidewall, the tire will carry the max load listed on the tire's sidewall at that pressure. If the door jamb sticker says 35 psi, then that's all that is required to carry the max rated load of the vehicle. Now whether you are over your max rated load with the trailer is another question....

Many report better stability via the stiffer tires running at the tire's max rather than the the mfrs inflation on the door jamb.

FWIW, this was exactly the issue with Ford and Firestone on the Explorers years ago...Ford rated the Explorer with a low GVWR and spec'd tire pressure to match. The roominess of the SUV had folks unknowingly overloading their Explorers and causing blowouts which were blamed on the tires since nobody actually weighed their SUVs packed full of stuff. Firestone's response was that the tires should have been inflated to the max sidewall pressure, not the lower number on the door jamb.

So (these numbers are just to illustrate) if the tire's sidewall says it can carry a max load of 2000 lbs at max pressure of 44 psi, but the vehicle manufacturer specs a rear axle rating (RAWR) of 3000 lbs, each tire only needs to carry 1500 lbs when the axle is at max capacity. So the vehicle mfr can spec a pressure of say 35 psi on the door jamb, since the tire will safely carry 1500 lbs at 35 psi.

Increasing the tire pressure from the vehicle's specified 35 psi to the max on teh sidewall will increase the carrying capacity of the tires but NOT the vehicle.

[APT]

It is my 2011 Chevrolet Suburban 2500. The overall tire sizes are the same, 265/75R16 and 265/70R17.

[FastEagle]

Bobbyg2013 wrote:
should I increase the rear tire pressure by 10 psi, on my truck's tires or leave at the suggested 35 psi that is shown on the sticker on the door jam?

What does your owner's manual say?

35 psi is normally for a standard load Passenger tire. Is there something on the sidewall that says you can go higher than 35 psi?

FastEagle

[CGRetired]

Also interesting to note in that sticker picture...the spare is a 16 inch tire and the rest are 17 inch...? Interesting...what kind of vehicle is that?

[MarkTwain]

Thsldo wrote:
I also experienced a squishy feeling when towing with the trucks suggested PSI. Once I aired up to the sidewall max, towing was night and day. Trailer tires, aired to the max, truck front and rear aired to the max. I keep it like that during the camping season, and then drop it back down to the truck recommended after the camping season is over, or if I am going on a trip without the camper. As for the rough ride, it's barely noticeable.

Recommend "E' rated tires and if possible 16" wheels.

[rbpru]

My 2011 F-150 4X4 came with the standard Wrangler 275/65r 18 Type P tires. I have 33,000 miles on them about 11,000 towing miles. They have a max pressure of 44 psi. stamped on the side wall, I tow with 40 psi rear and 38 psi front and have had no towing issues with a 5000 lb. dry weight TT.

I expect to get another season out of them then I thought I might switch to LT type tires. Some have even recommended load range “E” replacements.

A quick look at the truck specs shows the following, the front axle is rated for 3750 lbs. the rear axle is rated for 3850. Each of the P type tires have a 2601 lb. max rating stamped on the side wall for a combined rating of 5201 lbs. This puts the tire ratings 1400 lbs. over the axle rating.

A pair of load range Ds would provide an additional 45 lbs. of load capability and load range Es would give me 2234 lbs. more capacity than the TV axle rating and of course have no effect on the max cargo capacity.

Now I understand that because of sway, proposing or a general squishy feel, some people want the benefit of the added sidewall stiffness of the higher load range tires. However I consider my towing performance quite good and the ride of the TV when not towing more than firm enough without adding stiffer tires.

I suspect I will stick with what the TV maker recommends, they have been at it a long time.

[Thsldo]

I also experienced a squishy feeling when towing with the trucks suggested PSI. Once I aired up to the sidewall max, towing was night and day. Trailer tires, aired to the max, truck front and rear aired to the max. I keep it like that during the camping season, and then drop it back down to the truck recommended after the camping season is over, or if I am going on a trip without the camper. As for the rough ride, it's barely noticeable.

[coolbreeze01]

APT wrote:
This sticker lists what the vehicle manufacturer recommends for tire pressures as a compromise of ride/handling and comfort. It also must be capable of handling the vehicle's load at GVWR.



Many people have experienced that a little higher pressure when the vehicle is closer to GVWR than unloaded provides a better ride and handling.

Worth noting that the spare is filled to 80psi. Curious what the OP's spare tire is aired too?

[gmw_photos]

My little truck ( Nissan Frontier ) has "P" tires. Normal inflation is 35 psi. Max on the sidewall is 44. I tried 44 on the rear while pulling the trailer and discovered that was over-inflated. Even loaded up, the outside rib of the tires was not touching the pavement.
I settled on 36 front and 38 rear in my case, and this seems to work well. The truck handles correctly, the tires wear evenly, and run cool even on hot days at highway speed all day.
Y'alls mileage, tires, pressures and experience may vary.

As for "squishy handling", the biggest change I noticed regarding that was removing the load range C ST tires from the trailer, replacing them with load range D LT tires. Much better towing experience.

EDIT: another improvement to the stability of the towing with this combo was replacing the OE shocks on the back of the truck. I installed monroe sensa-tracs at first, and they were an improvement. I have since replaced those with billstein 5100's, and those were another step up in improvement.

[RJCorazza]

I generally avoid the tire pressure threads, but weighing in on P rated tires in general:
With the loaded weights of tow vehicles, running P rated tires can make for a less than desirable towing experience. If the OP has P rated tires and is not able or willing to upgrade them, then I personally would air up to the max sidewall pressure. In practically all other cases I air up based upon actual loads using the tire manufactures load table. IMHO, YMMV

[APT]

This sticker lists what the vehicle manufacturer recommends for tire pressures as a compromise of ride/handling and comfort. It also must be capable of handling the vehicle's load at GVWR.



Many people have experienced that a little higher pressure when the vehicle is closer to GVWR than unloaded provides a better ride and handling.

[2oldman]

A small truck then.. got it.